THERMAL SCIENCE

International Scientific Journal

Mohamed Braikia

,

Larbi Loukarfi

,

Ali Khelil

,

Hassan Naji

IMPROVEMENT OF THERMAL HOMOGENIZATION USING MULTIPLE SWIRLING JETS

ABSTRACT
The aim of this study is to examine different blowing configurations of multiple swirling jets for use it in terminal units of ventilation applications. The influence of several parameters such as the inclined vanes of diffuser and the sense of rotation of the single or multiple swirling jets, their number and their arrangement on the flow resulting dynamically and thermally is experimentally investigated. Flow rate was adjusted at Reynolds numbers, Re0, ranging from 104 to 30.103. The current study is carried out under uniform heat flux condition for each diffuser at Reynolds number of 30.103, the air being the working fluid. Experiences concerning the fusion of several jets show that the resulting jet is clearly more homogenized under swirling influence. The findings of this study show that the gap between the jets and their sense of rotation relative to the central jet, affects the quality of the homogenization of ambiance. Among the studied different configuration, the one which consists of a swirling central jet controlling the behavior of six swirling jets in counter-rotation is shown to be the most effective in terms of thermal destratification.
KEYWORDS
multiple free jets, swirling flow, thermal homogenization, Vanes swirler, ventilation improvement, air blowing
PAPER SUBMITTED: 2010-10-26
PAPER REVISED: 2011-11-04
PAPER ACCEPTED: 2011-11-30
DOI REFERENCE: https://doi.org/10.2298/TSCI101026131B
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2012, VOLUME 16, ISSUE Issue 1, PAGES [239 - 250]
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Improvement of thermal homogenization using multiple swirling jets

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